[Histonet] refrigerating sliver and gold chloride??

[Bonner, Janet]

I wonder if 'storing these reagents in the refrigerator' concept originated with the idea of 'keeping them in the dark'.
 
Janet 

________________________________

From: histonet-bounces <@t> lists.utsouthwestern.edu on behalf of John Kiernan
Sent: Fri 8/21/2009 5:00 PM
To: Cheri Miller
Cc: histonet <@t> lists.utsouthwestern.edu; histonet-bounces <@t> lists.utsouthwestern.edu
Subject: Re: [Histonet] refrigerating sliver and gold chloride??



There was never any reason to refrigerate "gold chloride" or silver nitrate. These compounds (solid or dissolved) can be kept for many years at room temperature.

If the solutions are used repeatedly they eventually deteriorate from contamination with bits of sections, causing a changed appearance. Gold solutions take on a greenish grey hue and flakes of metallic gold eventually settle out. These can easily be recovered and recycled to make "gold chloride" (HAuCl4) again. Clean "gold chloride" solutions keep for ever. I have a few bottles of 0.5% that are still that beautiful yellow colour after about 25 years.

Old silver nitrate looks a bit grey, not completely colourless. Re-purifying in a histology lab isn't really feasible. You can precipitate out and collect the silver, but (strangely) refining companies don't want it. Your message mentioned "silver and gold chloride". I don't know a histological use for silver chloride, which is very sensitive to light - goes grey-violet as you look at it.

John Kiernan
Anatomy, UWO
London, Canada
= = =
----- Original Message -----
From: Cheri Miller <cmiller <@t> physlab.com>
Date: Friday, August 21, 2009 12:10
Subject: [Histonet] refrigerating sliver and gold chloride??
To: "histonet <@t> lists.utsouthwestern.edu" <histonet <@t> lists.utsouthwestern.edu>
Cc: "histonet-bounces <@t> lists.utsouthwestern.edu" <histonet-bounces <@t> lists.utsouthwestern.edu>

> I just noticed that my silver and gold chloride says to store at
> room temp now. I have always stored them in the refrigerator. Is
> anyone still doing this?? Old habits die hard. I want to know if
> this has caused any staining issues for anyone.
>
> Cheryl Miller HT (ASCP)
> Histology Supervisor
> Physicians Laboratory,P.C.
> Omaha, Ne.
> 402 738 5052
>
>
> ________________________________
> PRIVILEGED / CONFIDENTIAL INFORMATION may be contained in this
> message. If you are not the addressee intended / indicated or
> agent responsible for delivering it to the addressee, you are
> hereby notified that you are in possession of confidential and
> privileged information. Any dissemination, distribution, or
> copying of this e-mail is strictly prohibited. If you have
> received this message in error, please notify the sender
> immediately and delete this email from your system.
> _______________________________________________
> Histonet mailing list
> Histonet <@t> lists.utsouthwestern.edu
> http://lists.utsouthwestern.edu/mailman/listinfo/histonet
_______________________________________________
Histonet mailing list
Histonet <@t> lists.utsouthwestern.edu
http://lists.utsouthwestern.edu/mailman/listinfo/histonet



=======================================================
The information contained in this message may be privileged and/or confidential
and protected from disclosure.  If the reader of this message is not the intended 
recipient or an employee or agent responsible for delivering this message to the 
intended recipient, you are hereby notified that any dissemination, distribution 
or copying of this communication is strictly prohibited.  If you have received this
communication in error, please notify the sender immediately by replying to this 
message and deleting the material from any computer.
=======================================================